Preparation of lubricants



Patented June 18, 1940 UNITED STATES PREPARATION OF LUBRICANTS John M. Musselman and Herman P. Lankelma, Cleveland, Ohio, assignors to The Standard Oil Company, Cleveland,

Ohio

Ohio, a corporation of No Drawing. Application November 26, 1937, Serial No. 176,664

4 Claims.

We have found that if a lubricant be made up with certain compounds, the result is a remarkably durable product, which is all the more surprising inasmuch as the constituents do not indicate such result-possibility. A mineral oil is employed as a base, and with it in composition a small amount of a salt of an N-substituted p-aminophenol (as for instance p-butyl aminophenol, p-benzyl aminophenol, and the like) with an organic carboxylic acid of at least six carbon atoms, (such acid being for instance a fatty acid of at least six carbon atoms, a naphthenic acid, or a halo-carboxylic acid, fatty acid or naphthenic) as p-butyl aminophenol stearate, p-butyl aminophenol laurate, p-butyl aminophenol palmitate, p-butyl aminophenol oleate, p-benzyl aminophenol laurate, p-benzyl aminophenol stearate, p-benzyl aminophenol palmitate, p-benzyl aminophenol oleate, p-butyl aminophenol naphthenate, p-benzyl aminophenol naphthenate, p-butyl aminophenol chlorostearate, p-butyl aminophenol dichlorostearate, p-benzyl aminophenol dichlorostearate, p-benzyl aminophenol chlorostearate, p-benzyl aminophenol chloronaphthenate, p-butyl aminophenol chloronaphthenate, etc. The amount of the salt employed need not generally exceed one per cent, based on the oil, and may usually be one-tenth to one per cent.

The compounds such as pointed out above may be prepared in suitable manner, as for instance by heating together equimolar quantities of the N-substituted p-aminophenol and the acids to be employed, in a suitable solvent, as for instance isopropyl alcohol about ten parts. Heating in a Ill) steam bath for about 5 minutes or slightly more, is in general suflicient for the reaction. The isopropyl alcohol or other solvent is then removed by evaporation, and the formed compound is ready for incorporation with the petroleum.

As an example: A Mid-Continent S. A. E. 30 oil is compounded with 0.1 per cent of monobenzyl p-aminophenol dichlorostearate. This product when operated as an internal combustion engine lubricant, under severe engine operating conditions, viz. head temperature 500 F., and jacket temperature 212 F., after fifty hours of continuous operation showed only 0.30 per cent sludge operation, whereas the oil with mono-benzyl p-aminophenol per se showed 0.40 per cent sludge, and the oil with dichlorostearic acid per se showed 4.00 per cent sludge. Furthermore, in the last two instances rings in the engine stuck, while in the lubricant with the 'mono-benzyl p-aminophenol dichlorostearate no piston rings stuck, but the engine continued to be highly satisfactorily lubricated.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims, or the equivalent of such, be employed.

We therefore particularly point out and dis-- tinctly claim as our invention:

l. A lubricant comprising a mineral lubricating oil and a small amount of a salt of an N-substituted p-aminophenol and an organic carboxylic acid of at least six carbon atoms.

2. A lubricant comprising a mineral lubricating oil and a small amount of a salt of an N-substituted p-aminophenol and a fatty acid of at least six carbon atoms.

3. A lubricant comprising a mineral lubricating oil and a small amount of a salt of an N-substituted p-aminophenol and naphthenic acid.

4. Alubricant comprising a mineral lubricating oil and a small amount of a salt of an N-substituted p-aminophenol and an organic halo-carboxylic acid of at least six carbon atoms.

JOHN M. MUSSELMAN. HERMAN P. LANKELMA.

CERTIFICATE OF CORRECTION.

Patent No. 2,20 ,172. June 1 191p.

JOHN M. MUSSEIMAN, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Second column, line 111., for the word "operation" read -fomation; and that the said Letters Patent shou ld be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 25rd day of July, A. D. 19140.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents. 

